C56.9
Malignant neoplasm of unspecified ovary
Billable FY2026 2025-10-01 → 2026-09-30
This is the unspecified option. 3 more
specific codes sit alongside it. Worth
checking whether the documentation supports one of them.
Instructional notes 9
C56code
Use additional code
- code to identify any functional activity
C00-D49chapter
Notes
- Functional activity
- All neoplasms are classified in this chapter, whether they are functionally active or not. An additional code from Chapter 4 may be used, to identify functional activity associated with any neoplasm.
- Morphology [Histology]
- Chapter 2 classifies neoplasms primarily by site (topography), with broad groupings for behavior, malignant, in situ, benign, etc. The Table of Neoplasms should be used to identify the correct topography code. In a few cases, such as for malignant melanoma and certain neuroendocrine tumors, the morphology (histologic type) is included in the category and codes.
- Primary malignant neoplasms overlapping site boundaries
- A primary malignant neoplasm that overlaps two or more contiguous (next to each other) sites should be classified to the subcategory/code .8 ('overlapping lesion'), unless the combination is specifically indexed elsewhere. For multiple neoplasms of the same site that are not contiguous, such as tumors in different quadrants of the same breast, codes for each site should be assigned.
- Malignant neoplasm of ectopic tissue
- Malignant neoplasms of ectopic tissue are to be coded to the site mentioned, e.g., ectopic pancreatic malignant neoplasms are coded to pancreas, unspecified (C25.9).C25.9
Index entries leading here 15
- Adenocarcinoma — see also Neoplasm, malignant, by site
- Adenofibroma
- Androblastoma
- malignant
- unspecified site
- female C56.9
- unspecified site
- malignant
- Arrhenoblastoma
- malignant
- unspecified site
- female C56.9
- unspecified site
- malignant
- Cystadenoma — see also Neoplasm, benign, by site
- papillary
- pseudomucinous
- serous
- mucinous
- Tumor — see also Neoplasm, unspecified behavior, by site
- Brenner D27.9
- malignant C56
- dermoid — see Neoplasm, benign, by site
- with malignant transformation C56
- yolk sac — see Neoplasm, malignant, by site
- unspecified site
- female C56.9
- unspecified site
- Leydig cell — see Neoplasm, uncertain behavior, by site
- malignant — see Neoplasm, malignant, by site
- unspecified site
- female C56.9
- unspecified site
- malignant — see Neoplasm, malignant, by site
- polyvesicular vitelline
- unspecified site
- female C56.9
- unspecified site
- granulosa cell D39.1
- malignant C56
- granulosa cell-theca cell D39.1
- malignant C56
- mucinous of low malignant potential
- unspecified site C56.9
- papillary — see also Papilloma
- serous of low malignant potential
- unspecified site C56.9
- Brenner D27.9
- Cancer — see also Neoplasm, by site, malignant
- ovarian C56.9
- Sertoli cell
- Leydig cell
- carcinoma
- unspecified site
- female C56.9
- unspecified site
- carcinoma
- Carcinoma (malignant) — see also Neoplasm, by site, malignant
- Cystadenocarcinoma — see Neoplasm, malignant, by site
- serous
- endometrioid — see Neoplasm, malignant, by site
- unspecified site
- female C56.9
- unspecified site
- mucinous
- papillary
- pseudomucinous
- Dermoid (cyst) — see also Neoplasm, benign, by site
- with malignant transformation C56
- Dysgerminoma
- unspecified site
- female C56.9
- unspecified site
- Teratoma (solid) — see also Neoplasm, uncertain behavior, by site
- ovary — see D27.-
- embryonal, immature or malignant C56
- ovary — see D27.-
- Thecoma D27
- malignant C56
Alongside this code 3 same parent — C56
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.